Attention-deficit hyperactivity disorder (ADHD) is one of the most common childhood neuropsychiatric conditions. Both (epi)genetic and environmental factors are suggested to contribute to the aetiology of ADHD. In the last decade, nutrition has received considerable attention as potential environmental factor triggering ADHD behaviour. Studies applying a few-foods diet (FFD) can lead to behavioural improvements of at least 40% in 50-64% of children with ADHD. It is conceivable that the Microbiota-Gut-Brain (MGB) axis is involved in the mechanism of action underlying the behavioural improvements observed in children with ADHD after following the FFD. This study investigated potential associations between changes in ADHD symptoms in children that followed an FFD. We identified a significant association between microbiota composition and change in ADHD symptoms in food-associated ADHD.

The authors have declared no competing interest.

NCT03440346

This study was funded by the Porticus foundation, which was not involved in study design and execution, data analysis and its interpretation, writing the manuscript and the submission for publication.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The Medical Research and Ethics Committee of Wageningen University gave ethical approval for this work (NL63851.081.17, application 17/24).

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Yes

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Yes

All data produced in the present study are available upon reasonable request to the authors